This is to bring to your notice about the indigenous
efforts of Indian scientists who developed a mass spectrometer based
payload called CHACE for which I was the team leader. This was done during
2003-2008 at Vikram Sarabha Space Center of ISRO, India.
My core team was comprising of 5-young members
below 30-years of age. Though, the ISRO like an ocean supported every
bit of realization of CHACE. The feeling of seeing your instrument reaching the
moon was so compelling that we were always walking an extra mile to
reach our targets. We wrote to many many experts: Alan Stern(e-mail),
who had written the review paper on the lunar constituents, Bob Hodges
(Postal letter) who had built LACE in the Apollo mission. We got immense
amount of information from both of them. Today, we owe a major
chunk of our success to all the wisdom we gained from these selfless humans who
worked very hard to explore the stellar bodies. I remember in one of Lunar
Exploration Conference (ILWEG-2007, Sorrento,Italy), one Apollo team scientist
was thanking god for hoping to see many more probes (ChangE-China,
Chandrayaan-I-India) bringing wealth of new data from the fascinating heavenly neighbor.
We figured that though detected night time
constituents of lunar constituents (for almost 8-months) the problem LACE faced
in detecting the day time concentration of the ambient constituents was
due to the large time slot assigned to collect each channel of data.
Though the calculation was correct but due to the low dynamic range of
their detection system, the detectors were "swarmed as the day
kicked in" to quote Alan Stern.
Our detector had 8-orders of dynamic range; thanks
to the present day technology; every decision of freezing the instrument
parameter was challenged and final conclusion arrived only after a
logical understanding of the issue, thanks to the ISRO culture.
On November-14th, 2008; when the Moon Impact Probe
(of Chandrayaan-I) data was
transmitted back, the peak at 18 (H2O) was literally "pouring
out" of CHACE. Our director, who was nearing 60, was jumping like a kid; we couldn’t believe for a while whether it
was all true.
We tried very very hard to publish this
"direct evidence of water" for the next 15-months; but nobody
believed us. We could bring to publication only in Feb-2010; and even
today many experts around the globe are unaware of the wonderful set of data
CHACE payload has achieved.
Please do have a reference of those papers we have
published; in case you find it interesting; you may please read the
following blogs as well.
R. Sridharan, S.M. Ahmed, Tirtha Pratim Das, P.Sreelatha, P. Pradeepkumar, Neha
Naik, Gogulapati Supriya
The sunlit lunar atmosphere: A comprehensive study by CHACE
on the Moon Impact Probe of Chandrayaan-1
R. Sridharan, S.M. Ahmed, Tirtha Pratim Das, P.Sreelatha, P. Pradeepkumar, Neha
Naik, Gogulapati Supriya
Direct evidence for water (H2O) in the sunlit
lunar ambience from CHACE on MIP of Chandrayaan-I, Planetary and Space
Sciences,58, 947-950, 2010
